This study will evaluate intensive relaxation therapy as a nonpharmacological treatment of asthma, using results of methacholine challenge testing as the primary measure of asthma. Large vs. small airway involvement in asthma (as assessed by heliox testing) and emotional contributions to asthmatic symptomatology (assessed by questionnaire) will be examined as predictors of response to treatment. Pilot data suggest a response to treatment on the methacholine challenge that is stronger than that found in static spirometry assessment. Also, relaxation therapy appears to be an effective treatment for asthma accompanied by large airway, but not small airway, obstruction. This study will examine these relationships in a controlled study with an adequate n. The relationship between large airway asthma and the psychosomatic contribution to asthma also will be studied. Thirty asthmatic subjects between the ages of 18 and 65 will be assigned to each of three experimental groups, matched on asthma severity and relative large vs. small airway obstruction. The groups will be progressive relaxation, self-relaxation-and-music placebo, and waiting list. Subjects in the relaxation and placebo groups will receive 8 sessions of small group treatment, approximately 1 1/2 hours in length, twice weekly. Pretraining and post-training, subjects will be administered the SCL-90R, and questionnaire measures of the emotional, physical, and respiratory precursors of an asthmatic attack and the degree to which subjects expose themselves to precipitant stressors. At Sessions 1, 4, and 8 (or 3 times for Waiting List Group, spaced approximately every 2 weeks) subjects will be administered an asthma symptom questionnaire as well as pre-session and post-session measures of FEV-1, heliox flow mechanics, and resting surface EMG from the frontalis laryngeal and dominant trapezius areas. A brief daily questionnaire includes measures of drug usage, symptomatology, medical interventions, and exposure to situations that tend to trigger symptoms. Subjects will assess their peak flow twice daily using a hand-held peak flow meter. Expectancies will also be assessed. Follow-up data will be taken for six months following post-treatment testing, and, at the six-month period, methacholine and heliox data again will be taken as well as the various questionnaire measures given at posttest. S's will receive subsidized medical care to maximize motivation and standardization.